piezoelectric actuators are widely used in micro manipulation applications. however hysteresis nonlinearity limits accuracy of these actuators. this paper presents a novel approach utilizing a piezoelectric nano-stage as slave manipulator of a teleoperation system. the prandtl-ishlinskii (pi) model is used to model actuator hysteresis in feedforward scheme to cancel out this nonlinearity. a pas...

Hydraulic machines have been widely used in a variety of high power applications. Typically these machines are operated by an operator. In past research the interaction safety between the operator and the machine was seldom investigated. This dissertation addressess the interaction stability issue by exploiting the safety guarantees offered by passive systems. The hydraulic machine considered i...

objective(s)previous studies have shown that vitamin b as well as folate supplementation has been implicated in cognitive and neurodegenerative disorders including alzheimer’s and parkinson's diseases. the aim of present study was to evaluate the effects of folic acid on passive avoidance task and motor coordination in healthy adult male rats.materials and methodsanimals were randomly divi...

In this paper, a passive bilateral control law is proposed for a teleoperator consisting of a pair of n-DOF nonlinear robotic systems. The control law ensures energetic passivity of the closed-loop teleoperator with power scaling, coordinates motions of the master and slave robots, and installs useful task-specific dynamics for inertia scaling, motion guidance and obstacle avoidance. Consequent...

AbstnactIn this paper, a teleoperation controller Is proposed for a-pair of nonlinear master and slave manip ulators. The control law enables the nonlinear robots to be perfectly coordinated despite arbitrary environment and human forcings, while ensuring that the closed loop teleop erator system is passive with respect to a supply rate that includes a user specifled bilateral power scaling fac...

Three sources of interlimb interactions have been postulated to underlie the stability characteristics of bimanual coordination but have never been evaluated in conjunction: integrated timing of feedforward control signals, phase entrainment by contralateral afference, and timing corrections based on the perceived error of relative phase. In this study, the relative contributions of these inter...

Passive systems possess the beneficial properties of ease of human control, and stable interaction with arbitrary passive systems. Motivated by these properties, our research has been directed towards developing passive hydraulic systems. A novel hydraulic element called the passive valve was first developed. The passive valve was used in single degree of freedom passive bilateral teleoperation...

acts with both the work environments and the huThe control of a bilateral teleoperated manipulator system is considered. The goal of the control are to i) coordinate the motions of the two manipulators according to a prede ned kinematic scaling, ii) render the dynamics of a locked system, and its response to forces from the human operator and environment to approximate that of prede ned natural...

The attitude coordination control problem for formation flying spacecraft associated with time-varying reference attitude tracking subject to control input saturation is investigated in this paper. According to different cases, three kinds of continuous and bounded coordination controllers are proposed. With the use of hyperbolic tangent functions, a fundamental controller is presented for an i...

Bilateral teleoperators, designed within the passivity framework using concepts of scattering and two-port network theory, provide robust stability against constant delay in the network and velocity tracking, but cannot guarantee position tracking in general. In this paper we fundamentally extend the passivity-based architecture to guarantee state synchronization of master/slave robots in free ...